Magnetic disk drives are used to store and retrieve data in many electronic devices including computers, televisions, video recorders, servers, digital recorders, etc. A typical magnetic disk drive includes a head having a slider and a transducer with a read and write element that is in very close proximity to a surface of a rotatable magnetic disk. As the magnetic disk rotates beneath the head, a thin air bearing is formed between the surface of the magnetic disk and an air bearing surface (ABS) of the slider. The read and write elements of the head are alternatively used to read and write data while a suspension assembly positions the head along magnetic tracks on the magnetic disk. The magnetic tracks on the magnetic disks are typically concentric circular regions on the magnetic disks, onto which data can be stored by writing to it and retrieved by reading from it.
The slider is aerodynamically designed to fly above a rotating magnetic disk by virtue of an air bearing created between the ABS of the slider and the rotating magnetic disk. The ABS is the portion of the slider surface which is closest to the rotating magnetic disk, which is typically the head portion of the slider. In order to maximize the efficiency of the head, the sensing elements (i.e., the read and write heads) are designed to have precise dimensional relationships to each other. In addition, the distance between the ABS and the rotating magnetic disk is tightly controlled. The dimension that relates to the write function is known as the throat height and the dimension that relates to the read function is known as the stripe height. Both the stripe height and the throat height are controlled by a lapping process.
The lapping process is performed on row bars, which are rows of sliders/heads, and includes backside lapping followed by frontside lapping. During the lapping process, row bars are mounted on a separate lapping ring at each lapping operation using a separate double-sided adhesive film.
The row bar is first mounted on a first lapping ring at the backside lapping operation using a first double-sided adhesive film that is stuck to the row bar on one side of the film and stuck to the first lapping ring on the opposite side of the film. Once the row bars are attached to the first lapping ring using the first double-sided adhesive film, backside lapping is performed on the row bars. After the backside lapping is completed, the row bars are manually peeled off the first double-sided adhesive film by an operator using tweezers. After the row bars are peeled off the first double-sided adhesive tape, the row bars are cleaned. The row bars are then mounted on a second lapping ring at the frontside lapping operation using a second double-sided adhesive film that is stuck to the row bar on one side of the film and stuck to the second lapping ring on the opposite side of the film. Once the row bars are attached to the second lapping ring using the second double-sided adhesive film, frontside lapping is performed on the sides of the row bars that were not previously lapped using backside lapping.
A drawback to the lapping approach described above is that the row bars can be damaged or broken as they are manually peeled off the first double-sided adhesive film between the lapping operations. Another drawback is the lengthy cycle time for ring-to-ring transfer due to manually handling the row bars.
Therefore, what is needed is a system and method that reduces the amount of row bar handling and damage during lapping operations and results in increased yield and reduced cycle time at the row bar lapping operation.